Thanks for that link I looked at that website and saw that they were pins but completely missed that they were nylon I must be losing my mind
The specs say for engine serial # n90 with a no load speed of 2500 rpm . I think with the bigger injectors they had a lower rpm
No load RPM is always higher than loaded rpm. I'm pretty sure your engines are supposed to make 2350 rpms with a load WOT. They're very good running engines with N90 injectors. Crisp, clean, good throttle response. I ran a set of Covingtons that initially had 110's and the owner had 90's put in during the rebuild.
Covington, S&S, J&T and others were all called on for some more HP than DD delivered. If painted green; should be N90s. Not Green; could have anything for injectors, turbos, blower ratio or cam timing.
Then there ya go, N90 for sure. Nothing exotic. Just a solid & stock DDC engine. It does not get any better.